The present invention relates to an elastic absorbent article such as a sanitary towel, a panty liner or an incontinence pad, intended to be placed in the crotch region of an undergarment, which article has a longitudinal direction and a transverse direction and comprises a liquid-permeable inner layer and a liquid-impermeable outer layer and an absorption body enclosed between the said layers, in addition to which the article incorporates fastening means for securing the article in the undergarment.
Conventional sanitary towels and panty liners, and incontinence pads in the same order of magnitude, are provided with fastening means for holding the article in place in the undergarments of the user.
A known problem is that undergarments are stretched and can also be locally displaced under the movements which occur in the use of the undergarment and that the sanitary towel is in this case dragged along by the garment and displaced from its position directly in front of the genitalia of the user. This is a common cause of leakage of body fluid from sanitary towels in the lateral direction.
Sanitary towels of conventional type are not stretchable or elastic and, apart from being unable to imitate the movements of the undergarment, are not flexible with the body and can be felt to be stiff and uncomfortable for the user.
Undergarments are felt by the majority of users to be comfortable and flexible. It has been proposed to design sanitary towels such that they are stretchable and, suitably, also elastic, so that they can imitate the movements of the user and the undergarment and remain in the intended position.
In U.S. Pat. No. 5,713,884, for example, sanitary towels are described which are stretchable and, preferably, also elastic.
The stretchability of the sanitary towel should suitably correspond to the stretchability or elasticity of the undergarment. It has been shown that ca. 20% stretchability is sufficient for undergarments to allow them to imitate body movements made by a user. This is also discussed in U.S. Pat. No. 5,713,884.
In the said publication it is stated that, suitably, all materials included in the sanitary towel shall be stretchable and preferably also elastic. Yet an illustrative embodiment is also mentioned in passing, in which the included absorbent material is not stretchable, though it is stated, at the same time, that this embodiment is not preferred.
It is possible to produce a sanitary towel which, owing to its elasticity, can adapt to the movements which occur in the undergarments of the user.
On the other hand, it is difficult to find elastic materials which have sufficient absorbency and liquid holding capacity and other properties demanded of present-day absorption materials. It is, however, easier to find inner layers and outer layers which are elastic and which, at the same time, can manage their respective functions, such as permeability and dryness for the inner layer and liquid-tightness for the outer layer.
By dropping the requirement that the absorption core also be elastic, there is no need to seek special absorption materials which are elastic and which, at the same time, can meet the tough capacity requirements which are placed on absorption materials in present-day sanitary towels. It is instead possible to make an arbitrary choice from all available absorption materials.
A problem which has not hitherto received attention is the risk that a non-elastic absorption core might easily end up in the wrong position when exposed to forces arising from the elastic outer layers when these are elongated and fastened in the undergarment of the user. When forces are applied and the outer layers of the product (sanitary towel) are lengthened as the towel is positioned, it is very important for the user to know where the absorption body is placed in the product (sanitary towel). In other words, it is important to ensure that the absorption body of the towel ends up directly in front of the genitalia of the user.
As a result of the present invention, an elastic absorbent article of the type described in the introduction has been achieved, which article essentially eliminates the problems described above.
An absorbent article according to the invention is characterized in that the inner layer and the outer layer are elastic and in that the intermediate absorption body is non-elastic, in that the inner layer and the outer layer extend beyond the absorption body in the lateral and longitudinal directions and are mutually joined there, in that the absorption body is connected to at least one of the said inner and outer layers only in a central and small region and in that the region is visibly marked on the liquid-permeable layer.
Owing to the visible marking, the central part of the sanitary towel, and hence the absorption body, can be optimally placed in the undergarment so that the said central region ends up directly in front of the genitalia of the user.
Expediently, the marking is constituted by a color marking or pattern stamp. Other types of markings are naturally possible. The essential point is that the marking is easily visible.
The fastening means are constituted by bonding agent coatings applied at separate locations on the liquid-impermeable layer. This is important in order for the inner and outer layers of the sanitary towel to be elastically stretchable over intermediate regions which have no coating of bonding agent. Expediently, bonding agent coatings are applied in the four corner regions of the article.
As stated above, it is essential that the central, marked region of the sanitary towel ends up in the correct position.
According to a suitable embodiment of the invention, one region of the bonding agent coating is therefore also applied right opposite of the marking.
According to a further embodiment of the invention, wings are arranged to extend beyond the outer and inner layers in the lateral direction. The wings are provided with fastening means devices and are intended to be folded around the edge of the crotch section of the undergarment and fastened to the outside thereof when the sanitary towel is positioned.
One way of reducing the risk of edge leakage caused by deformation of the product during use is to provide the product with a pre-formed, anatomically matched elevation, which is intended to be placed against the genitalia of the user when the product is positioned. The intention is also, of course, that the product, with its elevation, will remain in the applied position during use. This is facilitated if the elevation or hump is designed such that it is rigid under normal usage stresses. According to a suitable embodiment, the product according to the invention is therefore characterized in that the absorbent body is convex in the direction of the liquid-permeable inner layer which is facing the user during use of the product and in that the marking is applied to the inner layer substantially on the top of the convex surface formed.
If the absorbent body is relatively rigid in comparison to the inner and the outer layer, the absorption body, since it is fastened to the inner and/or the outer layer only in a central region, will otherwise xe2x80x9cfloat freelyxe2x80x9d between the inner and outer layers. In embodiments in which the absorption body has an extent such that it is relatively wide and approaches in the lateral direction the bound-together outer edges of the inner and outer layers, the absorption body is suitably rounded in the corners in order to prevent the free corner sections of the absorption body from catching in the bound-together edge sections of the inner and outer layers.